The BLUP Index - not many people have heard of it, and even fewer understand
it. However, it is a very important tool used by the Swedes to maintain
and improve their excellent breeding program.
Simplistically speaking, the BLUP Index ranks the Swedish Warmblood stallions
based on a variety of criteria, and estimates the breeding value of each
stallion. The technical and scientific explanations can get very complicated,
and if you have a strong interest in statistics and estimation there are several
highly informed individuals in the SWANA organization that could provide you
with more information. However, if you are looking for a casual, simplified
explanation of the tool, then you are in the right place. If anyone notes any
errors with the explanations provided here, please contact me. The goal here is
to inform and educate.
What is it?
The BLUP Index is a method of statistical analysis and estimation developed
in 1948 by Dr. C.R. Henderson. The BLUP (Best Linear
Unbiased Prediction) estimation method allows for
estimation and adjustment for systemic environmental effects simultaneous to
prediction of breeding values. Therefore, the BLUP allows and accounts for
genetic differences between herds and generations. A BLUP rating is linear
because of the constant updating of the numbers and unbiased because there is
little room for subjective opinion. The resulting numbers allow breeders to make
informed predictions when choosing breeding stock.
The Swedes have been using the BLUP-Animal Model for almost 20 years to
predict breeding value of their stallions, and were the first in the world to
apply it to horses. Dr. Jan Philipsson, professor of Animal Breeding and former
president of the Swedish Warmblood Association, has worked extensively on
developing the BLUP Index for the Swedish stallions. Data for the BLUP
index has been collected since 1973. The index is divided into three
categories (exterior, gaits, jumping) and there is also a height index.
Who is in it?
The index includes only stallions located in Sweden/Europe. A stallion must
have at least 15 inspected offspring out of inspected mares in order to have
enough data to be included in the index. The fewer the number of offspring that
the index is based on, the less certain the results. The stallion's foal results
from outside of Sweden are not included in the index. Due to cultural
differences as well as the horse industry diversity and vast land mass of North
America, it is currently not possible to collect the data necessary to create a
BLUP Index for North American stallions. The Swedes have been testing young
horses for over 30 years, and have accumulated the results in their database
containing over 20,000 horses. They can proudly proclaim that 60% of horses age
3-6 participate in the testing. It's a matter of national pride. The North
American culture has not wholeheartedly embraced the performance testing and
mare inspections, and the horse industry is still trying to accommodate the
requirements for data collection. The SWANA organization is working diligently
with U.S. Equestrian, the Federation of North American Sport Horse Registries,
and other horse industry organizations to promote the use of the BLUP index, and
enable the proper collection of accurate, useful statistical data. For now, you
can use the BLUP Index to research sires in the pedigree of the horse of your
interest. This too can be helpful and quite fascinating. There were six
new stallions in the BLUP Index for 2002: Briar, Cardento, Cortus, D-Day, Lucky
Light, and Vermouth.
Why use it?
The BLUP Index can be used as a supplement to other information and insight,
but should not be relied on as a sole source. There are many intricate details
that go into a top-notch sport horse, and not all of them can be measured. The
BLUP Index is a valuable tool that provides surprisingly accurate breeding value
estimates. A "must-read" for every breeder.
The index is updated
annually, and is a valuable tool for breeders as well as those shopping for a
performance horse.
